docs: documentation rework + Vortex encoding-format specification #4777

Job	Run time
Rust tests (tsan)	6m 14s
Rust/C++ FFI tests (tsan)	1m 58s
Rust tests (miri)	1m 36s
Rust tests (asan)	6m 47s
Rust/C++ FFI tests (asan)	2m 13s
Mirror DuckDB to R2 / Resolve DuckDB version and check R2	7s
Mirror DuckDB to R2 / Mirror DuckDB ${{ matrix.archive }} to R2	-1s
DuckDB libraries available in R2	3s
Rust tests (coverage) (tests)	6m 29s
	25m 26s

Provide feedback